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Educate me on drag shocks.
#1386183
02/12/13 04:24 PM
02/12/13 04:24 PM
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Joined: Dec 2010
Posts: 409
PEI Canada
chromedome426
OP
mopar
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OP
mopar
Joined: Dec 2010
Posts: 409
PEI Canada
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Have a friend with a 68 B-body looking for advice on drag shocks.
His car can hook well on a perfect track, but most times it will hook and then let go.
His car is a 1968 Road Runner, 3400lbs, 500cid, CalTracs, Split Mono-leaf, Rancho 9 way adjustable rear shocks, Calvert 90/10 front shocks, 29x10 Hoosier slicks, 4:10 gears, .880 Dia(slant six)torsion bars, tubular upper control arms w/rod ends, and greasable lower control arm pins w/urethane bushings.
He just ordered a pair of the Firm Feel .820 Dia (drag race) torsion bars.
He is wanting to here some opinions about changing over to the AFCO racing shocks.
Thanks.
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Re: Educate me on drag shocks.
[Re: chromedome426]
#1386184
02/12/13 04:31 PM
02/12/13 04:31 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Afco are a better shock but he needs to make sure he has good front end travel... if he takes a video of the launch he can get a better idea of what is really happening... I'm thinking he is running out of front end travel and as soon as it tops out it falls back down to cause the spin... also when its on a lesser hooking track he needs to loosen up the rear shocks for more lift 
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Re: Educate me on drag shocks.
[Re: chromedome426]
#1386187
02/12/13 05:47 PM
02/12/13 05:47 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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At 5.25 travel he has plenty... myself I only use a single adjustable shock...I've always felt the compression (on a double adjustable) was for down track... the extension was for the starting line
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Re: Educate me on drag shocks.
[Re: MR_P_BODY]
#1386188
02/12/13 09:54 PM
02/12/13 09:54 PM
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Joined: Jul 2006
Posts: 4,319
Puyallup, WA
StealthWedge67
master
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master
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
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Seems to me that he's got all the right stuff there. I'm sure there's guys out there going fast and hooking hard with LOTS less than he has. Something else has to be at issue here. I'd be hesitant to just throw more money at it. What sort of performance levels are we talking about, here?  As said, Video will be needed before anyone here can really offer any good help.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
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Re: Educate me on drag shocks.
[Re: MR_P_BODY]
#1386189
02/12/13 10:17 PM
02/12/13 10:17 PM
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Joined: Oct 2003
Posts: 1,409
Ont. Canada
10.90 Racer
super street
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super street
Joined: Oct 2003
Posts: 1,409
Ont. Canada
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Quote:
Afco are a better shock but he needs to make sure he
has good front end travel... if he takes a video of
the launch he can get a better idea of what is really
happening... I'm thinking he is running out of front
end travel and as soon as it tops out it falls back
down to cause the spin... also when its on a lesser
hooking track he needs to loosen up the rear shocks
for more lift
What setting are the rear shocks on???
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Re: Educate me on drag shocks.
[Re: 10.90 Racer]
#1386190
02/12/13 11:28 PM
02/12/13 11:28 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Quote:
Afco are a better shock but he needs to make sure he
has good front end travel... if he takes a video of
the launch he can get a better idea of what is really
happening... I'm thinking he is running out of front
end travel and as soon as it tops out it falls back
down to cause the spin... also when its on a lesser
hooking track he needs to loosen up the rear shocks
for more lift
What setting are the rear shocks on???
I dont now why your asking me... its not my car
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Re: Educate me on drag shocks.
[Re: Irun5snd8th]
#1386192
02/13/13 12:33 AM
02/13/13 12:33 AM
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Joined: Dec 2005
Posts: 1,495
Shelby mi.
JAKE68
pro stock
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pro stock
Joined: Dec 2005
Posts: 1,495
Shelby mi.
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CalTracs want 1-3 neg degrees of pinion angle relative to the trans. Its hard to answer any questions you may have without knowing the cars set up. Like how much preload,what rear shocks are set at,what size tire and air pressure,top or bottom hole, how much converter,. Most of the average 10.30-10.60 et car would usually 60 in the 1.40-1.49. Some well sorted out will go much better. He has allot of good parts there so it is got to be just the set up or combo and not to throw more parts at it. We have stock front end with dbl adjustable afco's and we 60 1.28-1.32. So he allready has more then us. So there is some work to be done.Jake
JAKES AUTOMOTIVE
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Re: Educate me on drag shocks.
[Re: chromedome426]
#1386194
02/13/13 09:51 AM
02/13/13 09:51 AM
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Joined: Jan 2013
Posts: 167
maryland
74yellowduster
member
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member
Joined: Jan 2013
Posts: 167
maryland
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Quote:
When the track is perfect he can get 12 inches of air under the front tires and it will stay hooked even when the front comes back down. When the track is marginal he can only get 2 inches of air under the front tires. He does loosen the shocks for those conditions but feels that the rear shocks may need to be double adjustable. He is also wondering if the double adjustable front shocks would help?
this sounds like "when the track isn't perfect" his slicks don't hook.
it sounds like when they hook it works perfectly.
how much air is he running in them, how old are they, is he heating them up enough, can he go wider, etc.
it sounds like he has the suspension right, but he's spinning for some reason
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Re: Educate me on drag shocks.
[Re: chromedome426]
#1386195
02/13/13 10:15 AM
02/13/13 10:15 AM
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Joined: Jan 2003
Posts: 13,360
Marion, South Carolina [><]
an8sec70cuda
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 13,360
Marion, South Carolina [><]
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Try different front shocks, you might be surprised.
CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax
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Re: Educate me on drag shocks.
[Re: sshemi]
#1386196
02/13/13 02:44 PM
02/13/13 02:44 PM
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Joined: Dec 2010
Posts: 409
PEI Canada
chromedome426
OP
mopar
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OP
mopar
Joined: Dec 2010
Posts: 409
PEI Canada
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Unfortunately we don't have any video of the car. However, he will definately get some, once the 3 feet of snow melts off the track.  He sent me a few pictures that may or may not help for now. He has tried every setting on the shocks multiple times. He has set the bars in both the upper and lower holes. He has also played with preload to no preload on the bars. Slicks are 29x10 on 10" wheels and has 14 psi hot. The comment about pinion angle turned on a light bulb for him. That is something that he hasn't changed. I believe it's only at 2 or 3 degrees down. The car has run 10.25 at 132 mph in good air but mostly in the heat of summer it's 10.40's at 129 mph.
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Re: Educate me on drag shocks.
[Re: chromedome426]
#1386200
02/13/13 03:13 PM
02/13/13 03:13 PM
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Joined: Jan 2003
Posts: 13,360
Marion, South Carolina [><]
an8sec70cuda
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 13,360
Marion, South Carolina [><]
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Preferably an adjustable front shock, but anything tighter than the Calvert's will be better. I use some old Lakewood 90/10s that are a lot stiffer than the Calverts which are REALLY loose. Sounds exactly like what my car did after I put on the Calvert 90/10 front shocks. I got it to hook once on a very well prepped track and "treated" tires...it almost went on the back bumper. The very next pass it started to unload again. Put my old front shocks back on and it went right back to hooking like always. The front rises too fast, bottoms out, and unloads the rear. I put on new rear shocks, new tires, and every possible bar adjustment trying to fix it...didn't respond to anything. I never thought those Calvert shocks would be the problem b/c everyone says they're great, but I found out the hard way.
CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax
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Re: Educate me on drag shocks.
[Re: chromedome426]
#1386201
02/13/13 03:23 PM
02/13/13 03:23 PM
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Joined: Jan 2013
Posts: 167
maryland
74yellowduster
member
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member
Joined: Jan 2013
Posts: 167
maryland
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i cant tell too well from the pictures, but it doesnt look like he can go wider. is he 50/50 front to rear on weight? he might be able to go with a softer compound? HOOSIER CHART  MICKEY THOMPSON COMPOUND SELECTION CHART Medium----------------------------------------------------------Soft M7 X5 M5 M8 R1 L8 X7 L4
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